Safety switch for centrifugal machines



June 21, 1927,

, 1,633,039 LE ROY c. scHENcK SAFETY SWITCH FOR CENTRIF'UGAL MACHINESFiled Jan. 7, 1927 45 &\ r x \1 K 9 Y Z] 11 8 12 E Patented June 21,1927.

UNITED STATES PATENT oFFIcE;

LE 30"! O. SCHENCX, OF EAST IOLINE, ILLINOIS, ASSIGNOR '10 TROYLAUNDRYIL- OHILTEBY (30., LTD., 03 EAST MOLINE, ILLINOIS, A CORPORATION OF NEWTYORK.

SAFETY SWITCH. FOB CENTBIFUGAL MACHINES.

Application med-Januar 7, 1927. Serial in. 159,507.

The present invention relates safety switches for centrifugal machines.

' adapted to receive t The present invention is particularly useful andwill be described in connection with centrifugal extractors such as areused for extracting moisture from washed clothes. In a well known typeof extractor a basket pended. from above and given a movement ofrotation. In the event that the basket may be set up in the basket. Itas been customary for the operator to .watch his extractor for a shorttime after loading the machine and setting same in operation, to

make sure that the load was not too greatlyv out of balance. In casethe-operator should find that the load was too greatly out of balance,hewould stop the machine before it reached full speed and woulddistribute the goods more evenly. There have ,been instances, however,when the operator would load the basket, start the motor for. drivingsaid basket and walk away. If the basket were badly loaded, considerabledamage to the machine might result.

An object of the resent invention is to provide a safety switch for acentrifugal machine which switch,,.willresult in the eenergization of.thedriving motor in case g ations of more than a predetermined amwhichis sturdy, not like y to p itude are set up. I

A further object is.to provide a simple switch, which may be readilyattached to' centrifugal extractors as now commonly known and used.

A further object is to rovide a switch t out of order, and which may bemanu actured at relatively small cost. Referring to the drawin Figure 1is a sectional VIGW'Of the upper portion of a centrifugal extractorshowing one embodiment of the present invention applied thereto Figure 2is a detail view on an enlarged scale sho a rtion of the switchmechanism, said view ing taken along the plane indicated by the arrows2.-2 of Figure 1; an v Figure 3 is a view taken along the same plane asFigure 2 but looking in the opposite direction.

shaft of a centrifugal machine which shaft will be prevented fromrotating'at'danger- 110.

The numeral 1 indicates the rotatable e washed clothes is susrationstracted. A ve may have supported at the lower extremity thereof a basketof whirled to extract molsture therefrom. Said shaft is provided nearits upper extremity with a bushingv 2 having a portion 3 presenting aspherical surface constitutingpart of a universal joint. The sphericalportion code which are to be 3 is housed within a spherical bearingprovided by thetop castin 4 and the bottom castmg 5, said top castmg 4,in the illustrated embodiment of the present invention,

comprising a rigid portion of an extractor.

The bottom casting 5 is resiliently supported on the top casting 4 bymeans of the bolts f reason of this construction,

Keyed to the upper extremity of theshaft 1 is the cup-shaped member 8,which constitutes one member of a mechanical clutch,

the cooperating member ofwhich is indicated by the numeral 9.- Thenumerals 10-10 lndicate blocks housed within the clutch member 8, whichblocks under the effects of centrifugal force are adapted toflyoutwardly against the inner wall of said clutch member 8 to havegripping engagement therewith. The clutch member 9 is adapted to bedriven by any suitablesource of power, anelectric motor/ being preferredThe details of'the clutch, comprising the members 8, 9 and 10, need notbe described in detail, inasmuch as clutches suitable for the purposewill occur to those skilled in the clutch member 9 is driven at or abovea predetermined speed, the blocks 10 willoutwardly into gr'pping theclutch member 8, w ereby to communicate a driving movement 'to saidclutch member 8. Inasmuch as said clutch memi relationship wit art.Itniay be said, however, that when the bar 8 is keyed to the shaft 1, aturning movement will be communicated to said shaft 1. The shaft 1carries at or near its lower extremity a basket (not shown) for holdingthe goods from which moisture is be exserious problem in the opervweation of centrifugal extractors arises from unbalanced loads. Thepresent invention contemplates a structure whereby the shaft The switchbox 11 comprises a housing 13,:

which provides bearings for a rotatable shaft 14. Secured to said shaft14 is the arm 15, which has pivotally secured thereto the pair of switchcontact members 16-16, which are .electrically connected together.Mounted upon the housing 13 is a cover plate 17, which may be made ofinsulating material and which provides a support for a pair ofrelatively stationary switch contact members 18-18. A spring 19 isprovided, which in the illustrated embodiment of the present inventionis a coil spring disposed upon the shaft 14. Said spring has one of itsterminals in abutting relationship with the housing 13 and the other ofits terminals in abutting relationshipwith the arm 15. Said springnormally holds the switch members. 16-16 in contacting relationship withthe realtively stationary contact members 18-18.

Keyed to the shaft 14 is a lever 20, which lever has its end portionextendingv through an aperture 21 in'the casting 1 into proximity with.the clutch member .8.

The relatively stationary contact members 18-18 will'be connected in.the electrical circuit of the motor for driving the clutch member 9,whereby when the electrical connection between said contact members18-18 is broken, theelectrical circuit of the driving motor will beinterrupted. As noted above, the spring 19 normally holds the contactmembers 16-16 in contacting relationship with the members" 18-18.Inasmuch as said contact members 16-16 are connected together, anelectrical connection is normally provided between the contact members18-18. In case undesirable gyrations should be set up in the shaft 1,the clutch member 8 will be moved out of the symmetrical position inwhich it is illustrated in Figure 1, into. contacting relationship withthe lever 20. This movement will result in movement of the lever 20,which in turn results in disengagement of contact members 1616 from thecontact members 18-18, breaking the electric circiut of the drivingmotor.

According-to the illustrated embodiment of the present invention,interruption of the electric circuit of the driving motor will be onlytemporary, the spring, 19 automatically moving the. contact members16-16 into contact making position when the clutch member 8 is again ator near its symmetrical position. The net effect is, however, that itwill be'impossible for the clutch member and shaft 1 to acquire avelocity such as will prolever. 20 has been moved outwardly by the 7clutch member 8, the contact members 16-16 will be held out of engagingrelationship with the contact members 18-18 until the operator has givenattention to the machine and taken some positive steps to bring the 7contact members 16-16 into en agingwrelationship with the contact memers 18-18.

Though the illustrated embodiment of the present invention shows thelever 20 to be in position to be operated by the clutch 111cmher 8, itwill be understood thatsaid lever 20 may be located in position to beoperated by any other part of the machine which is subject toundesirable gy'rations. Many other modifications will occur to thoseskilled in the art. It is intended to cover all such modifications thatfall within the scope of the appended claims.

What is-clalmed is- 1. In a centrifugal machine, incombination, arelatively fixed housm a rotary member within said housing, an anelectric switch carried by said housing for controlling the rotation' ofsaid rotary member, said switch having means adapted to be engaged bysaid rotary member to open said switch when said rotary member acquiresundesirable gyrations.

2. In a centrifugal machine, in combination, a relatively fixed housin arotary I00 memberwithin said housing, an an electric switch forcontrolling the rotation of said rotary member, said switch having meansadapted to be engaged by said rotary memher to open said switch whensaid rotary member acquires undesirable gyrations, said switch beingmounted upon the outside of said housing and havin said means extendingthrough the wall 0? said housing to the interior thereofinto proximityto said ro- I tary member.

3. In a centrifugal extractor, in combination, a rotary shaft,supporting means for said shaft permitting a universal movement thereof,a. clutch member secured to said shaft, a complementary clutch memberfor communicating the movement to said first mentioned clutch member, anelectric switch for controlling the rotation of said complementaryclutch member, said switch having means adapted to be engaged by saidfirst mentioned clutch member too en said switch when said firstmentione clutch member acquires undesirable gyrations.

)1 5 4. In combinatioma relativel fixed housshaft, a complementary.clutch member adaptedto communicate rotary movement to sa id' ousi tudeare set up.

said first mentionedjclutch member, a switch for controlling themovement of said complementary clutch member, said switch being mountedupon the outside of said housing and havin means extending through thewall of mentioned 0 utch member in position to be engaged by said firstmentioned clutch member when gyretions of predetermined ampli- -intoproximity to said first 5. In a centrifugal machine, in combine tion, arotarytshaft subject to gyrations, an electric switch for controllingthe rotation of said shaft, said switch having means adapted tobe'engaged by said shaft when gyrations of predetermined amplitude areset up.

Signed at East Moline, Illinois, this- 3rd day of January 1927.

in ROY c. SGHENCK.

